I’m talking compatibility of displaing documents more than anything else, since even different versions of Word display the same document differently sometimes.
But the closest worlflow would be nice. Preferably something like '03 MS Word Office. It was crude in many ways, but I just hate ribbon menus and love having anything at hand. Especially a style menu, customisable keybinds and batch-replace with regexps.
Is there’s something to get closer to that in FOSS, or just Linux-compatible apps?
Depends on the formatting, but LO has better support for the old MS Office formats than Microsoft does.
I would recommend opening up one if your files in LibreOffice and seeing if the formatting is how you set it up. The file itself won’t change until you save, so if you close the programming without saving, your file won’t get messed up if there are glitches. If you’re really worried, make a backup of the otiginal test file just in case.
We can provide suggestions, but you won’t make progress until you actually try it out.